A juvenile Marbled Murrelet (Brachyramphus marmoratus) sits on its nest platform high in an old-growth Douglas fir. The Marbled Murrelet is an endangered seabird. A recent study used age-ratio analysis of museum specimens collected from 1892-1922 to measure long-term demographic changes in this species. Researchers compared the long-term demography with contemporary estimates and predictions from life history theory. Historic reproduction rates estimated from the museum specimens matched predictions from comparative analysis, but it was 8–9 times greater than contemporary estimates. Adult survival was similar. Historic reproductive rates would support stable populations, but current rates should result in population declines. Using museum specimens to reconstruct historic demography is a unique method used to identify causes of decline and set benchmarks for the recovery of endangered species. This photograph originally appeared on the cover of Ecology (88:2) in February of 2007.